Which hanger? I have painstakingly drawn the TMP hanger and it fits perfecftly in the 1000' Refit. The TFF hanger Gary Kerr drew quite nicely and it also fits very well. The doors in the exterior view are a bit wonky, but the interior set fits. The interior of the TMP hanger was a matte painting with the cargo bay being the only thing filmed live. Andrew Probert, who drew out the deck placement, did the initial matte paintings and someone else did the final paintings. The difference is that Probert showed shuttles and the ones in the film did not.If you want the cargo deck to match what was shown on screen then the refit needs to be at least 1,164 feet long (as per Blssdwlf's excellent research). Such a size would also help fit in the long engine room corridor but it's not absolutely essential for that.
The downside of a 1,164' refit is that the airlock docking ports would be 8' in diameter instead of 7' and we see a lot more of the docking ports (both inside and out, in numerous movies) than we do the cargo deck.
So I don't know where the 1164 measurement comes from, but I don't agree with it. The TOS Enterprise is 947' and the TMP refit and the 1701A are 1000'. I don't accept any other lengths other than to ponder if certain sets might fit better as built, but for me, that size of the ship dictates the size of the realistic spaces. I posted both my Phase II and TMP Refit cross sections in another threat - https://www.trekbbs.com/threads/enterprise-evolution-from-tos-to-tmp.300617/page-7